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排序方式: 共有10000条查询结果,搜索用时 13 毫秒
991.
This study has shown that the retinae of Prototherian (egg-laying) mammals possess two neuronal types that are present in non-mammalian retinae, but absent or morphologically different in the retinae of Eutherian (placental) mammals. First, endogenous serotonin-like immunoreactivity has been localized in a population of presumptive amacrine cells in the platypus retina, the first such report in a mammalian retina. Second, the protein kinase C-immunoreactive (PKC-IR) bipolar cells in the echidna retina appear similar to the PKC-IR bipolars in the chicken retina, in that their dendrites give rise to a Landolt's club and their axons are multistratified. By contrast, the PKC-IR rod bipolar cells in the rabbit and in the brushtail possum, a Metatherian (marsupial) mammal, have no Landolt's clubs and their axons form terminal lobes in the innermost stratum of the inner plexiform layer. 相似文献
992.
The study examines whether the order of administering 2 doses of quinpirole (0.5 and 8 mg/kg) affects the development of behavioral sensitization, as measured by the amount of forward progression and mouthing. Results show that injection of the high dose greatly enhances the subsequent locomotor response to the low dose of quinpirole, but not vice versa. Mouthing activity is not influenced by order of administration but is significantly greater at the higher dose of quinpirole. The present findings are consistent with a hypothesis that locomotor sensitization involves down-regulation of a D1 tone normally inhibitory to D2 locomotor activation. 相似文献
993.
Scanning electron microscopic study on local cornea tolerance of beta-blocker eye drops with and without preservatives 总被引:1,自引:0,他引:1
H Brewitt 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》1990,201(3):152-161
The influence of beta-blockers in short- and long-term application on the epithelium of the cornea was studied in rabbits with intact tear film, concentrating not on the completeness of the drug group but on general differences. The new unpreserved beta-blocker timolol was compared on an exemplary level with the following beta-blocker formulas: (1) beta-blocker eye drops with 0.01% of the preservative benzalkonium chloride; (2) beta-blocker eye drops with 0.005% of the preservative benzalkonium chloride, and (3) beta-blocker eye drops with 0.004% of the preservative benzalkonium chloride and the tear substitute polyvinyl alcohol. Exposure time in the short-term test was 30 min, in long-term tests the time was 24 weeks. Any cell damages observed were of only minor importance and rarely of clinical relevance; however, it could be shown that micromorphological cell reactions differed as a function of the preservative concentration. Complete absence of preservatives causes no difference in micromorphologically relevant changes in comparison with the control group. Drugs without preservatives are thus a meaningful alternative for patients with allergies, sensitive eyes or existing impairment of the precorneal film. 相似文献
994.
J. P. H. DRENTH L. P. BOS L. G. J. B. ENGELS 《Alimentary pharmacology & therapeutics》1990,4(4):411-416
Calcium antagonist relax smooth muscle, a possible useful concept in treatment of diffuse oesophageal spasm. Therefore the effects of oral diltiazem (60 mg t.d.s.) and placebo were compared in eight patients with diffuse oesophageal spasm in a 10-week double-blind crossover study. The patients recorded the severity of chest pain and/or dysphagia in daily pain diaries using visual analogue scales. Chest pain index and dysphagia index were calculated by multiplying frequency with daily intensity of each individual symptom. When compared to placebo, diltiazem did not significantly change the overall dysphagia index and chest pain index. An individual sizeable reduction of dysphagia was attained on diltiazem in four out of six patients and in six out of eight patients suffering from chestpain. Side effects were not seen during diltiazem therapy. Diltiazem, in our study, did not yield in a significant improvement of symptoms in diffuse oesophageal spasm. Diltiazem, however, can offer relief in selected individual patients suffering from diffuse oesophageal spasm. 相似文献
995.
A series of 5-alkyl-5-phenylbarbituric acid analogues were shown to be potent hypolipidemic agents in rats and mice at 20 mg/kg/day. This dose is lower than that required for hypolipidemic activity for clofibrate and nicotinic acid derivatives in rodents and man. These new derivatives reduced both serum cholesterol and triglyceride levels in rodents by either the oral or intraperitoneal route of administration. Previous studies have demonstrated that similar heterocyclic compounds, i.e. cyclic imides, glutarimides and hydantoins are potent hypolipidemic agents in rodents. The barbituric acid derivatives probably interfered with de novo synthesis of cholesterol and fatty acids in the early steps since the agents inhibit the activities of ATP-dependent citrate lyase and acetyl-CoA synthetase. Triglyceride synthesis may be blocked since the agents inhibited the rate limiting enzyme, sn-glycerol-3-phosphate-acyl-transferase. Rat tissue lipids especially cholesterol and triglycerides were reduced after 14 days treatment. Fecal lipids were increased in cholesterol and phospholipid content by selected compounds. The rat serum lipoprotein after 14 days drug administration showed reduced VLDL-cholesterol and HDL-triglyceride contents. The modulation of the lipid content of the serum lipoproteins by the barbituric acids suggest that these agents may be helpful in treating clinical hyperlipidemic disease states. 相似文献
996.
997.
H. S. Markus A. M. Tomkins G. M. Stern 《Journal of neural transmission (Vienna, Austria : 1996)》1993,5(2):117-125
Summary An anthropometric study was performed in 95 subjects (53 male, 42 female) with Parkinson's disease. Weight, height, triceps and biceps skin-fold thicknesses, and mid-arm circumference were recorded. A high incidence of undernutrition was found (23.6% of males and 22.5% of females, as defined by recent British guidelines). A subgroup of severely disabled patients with Parkinson's disease had a significantly lower mean body mass index than a similarly disabled control group with chronic pyramidal upper motor neuron lesions (males 20.6v 23.2 kg/m2 p<0.05; females 20.6v 26.6 kg/m2 p<0.01), suggesting that the undernutrition is not due to chronic illness or immobility alone. Correlation between anthropometric indices and clinical features of disease demonstrated that the presence of moderate or severe dyskinetic movements was the clinical parameter most strongly related to undernutrition. The reduction in anthropometric indices was most marked for skin fold thickness (related to percentage body fat) and least for arm muscle circumference (related to lean body mass); therefore the weight loss seen in Parkinson's disease is primarily due to fat loss rather than muscle loss. 相似文献
998.
999.
Occupational diseases of the musculoskeletal system of the SUVA (Swiss Accident Insurance Institute)
H U Debrunner 《Der Orthop?de》1990,19(3):163-171
First there is given a definition of occupation related diseases of the musculoskeletal system as a subject to the Swiss federal law of social insurance. As a relation to age and sex, the incidence, the following time of work incapacity and the financial consequences of disability are reported within a period from 1970 to 1983. Although the results are highly specific to Swiss legislation, the international comparison might be of interest. 相似文献
1000.